Transcript the respiritory system - Watford Grammar School for Boys Intranet

Year 10 GCSE PE
RESPIRITORY SYSTEM
Body in Action
Today
How do we breath?
The Respiratory system
The respiratory system
We will aim to learn to:
Identify what the respiratory system is,
 Know what the respiratory system is made
up of,
 The functions of the respiratory system,
 How it works during exercise.
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The Respiratory System
So, what is the
respiratory system?
The respiratory system is
the system in your
body which allows
you to breath in air
and stay alive.
The Respiratory system
What makes up the
respiratory system?
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There are many parts to the
respiratory system these
are:
 The Nasal cavity
 The Epiglotis
 The Larynx
 The Trachea (wind pipe)
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The Bronchi (each one is a
bronchus)
The Bronchioles
The Alveoli
The Thoracic cavity
The Pleural membrane
The Ribs
The Intercostal muscles
The Diaphragm
The Respiratory System
The Respiratory System
functions
Each part of the RS has a
function these are:
 The Nasal cavity: Hairs in
the nose filter and mucus
warms and moistens the
air.
 Cilia: These are coarse
hairs that trap bacteria and
large dust particles and
send them down the throat
to be swallowed.
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The Epiglottis: This small
piece of cartilage prevents
air travelling down the
food pipe.
The Larynx: Makes sound
for speaking when air
passes through it.
The Trachea (wind pipe):
This is a large flexible
tube surrounded by rings
of cartilage to prevent it
from collapsing.
The Respiratory System
functions
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The Lungs: The 2 major
organs of the respiratory
system, they are soft,
moist, spongy air sacs.
The Thoracic cavity: The
space which the 2 lungs
occupy.
The Pleural membrane:
A Slippery skin lining
the cavity.A “protective
device”by stopping
friction between the
lungs and ribs.
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The Bronchi (each one is
a bronchus):These
branch air into each
lung.
The Bronchioles: The
Bronchi branch into
these and take air further
into the lungs,
The Alveoli: These are
tiny air sacs. There
walls are so thin so
gaseous exchange can
occur. When the lungs
contract the air sacs fill
and empty.
The Respiratory System
functions
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The Ribs: Protect the
lungs.
The Intercostal muscles:
Muscles between the ribs
which help you breathe.
The Diaphragm: Sheet of
muscle below the lungs
sealing of the chest from
the abdominal cavity
Movement of air when breathing
Breathing in:
Nasal Cavity / Mouth
↓
Trachea
↓
Bronchi
↓
Bronchioles
↓
Alveoli
↓
Blood
Breathing out:
Blood
↓
Alveoli
↓
Bronchioles
↓
Bronchi
↓
Trachea
↓
Nasal cavity / Mouth
The Alveoli
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The Alveoli is where
gaseous exchange occurs.
Found at the end of the
bronchioles, each smaller
than a grain of salt.
Have thin, moist walls to
help gases pass through.
They are covered with tiny
blood vessels called
capillaries. Gases pass
through the capillary
walls.
The Alveoli
Gaseous exchange
Task:
Copy out the labels and
label your diagram.
The picture opposite shows
what happens.
1.
Blood carries waste CO2
from body to Alveoli.
2.
CO2 passes through
capillary walls into
Alveoli.
Gaseous Exchange
3.
4.
5.
6.
CO2 travels out of lungs
and up windpipe, you
breathe it out.
You breathe in O2 and it
travels to the alveoli.
O2 passes through the
alveoli walls and into the
capillaries and blood
stream.
The blood carries the O2
away to the body cells.
How Air changes in the Lungs
Into the lungs:
 O2 = 21%
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CO2 = tiny
amount
Nitrogen (N2)=
79%
Water Vapour
(H20) = a little
Out of the lungs:
 O2 = 17% (reduced as
the body has used some)
 CO2 = 3% (increased as
body has produced some)
 Nitrogen (N2) = 79%
(body doesn’t use, but a
component of air)
 Water vapour (H20) = a
lot (increased as a by
product of aerobic
respiration)
Breathing
It’s the same principle
with a syringe and the
bellows.
Breathing in: (syringe)
we must first make the
volume of the thorax
(chest) larger, in order to
breathe in.
Breathing out: (bellows)
We must make the volume
smaller again in order to
breathe out.
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So how do we breathe in
and out?
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What happens to our
chest, what can you feel
happens?
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How does air travel in and
out during breathing?
Breathing In
To Inhale:
 Diaphragm muscle
flattens
 Intercostal muscles
contract lifting rib cage
up.
 Thorax volume increases.
 Decrease in atmospheric
pressure in the lungs = air
sucked in.
 An Increase in Volume = a
decrease in pressure – air
enters.
Breathing Out
To Exhale:
 Diaphragm muscle
relaxes.
 Intercostal muscles relax,
 Ribs relax and fall.
 Thorax volume decreases.
 Increase in atmospheric
pressure in the lungs =
forcing air out.
 A decrease in volume =
increase in pressure – air
is forced out.
How Much air do we breathe
Tidal Volume: The amount of
air you breathe in or out
each breath (breathing
deeply increases this).
 Minimum = 3ml/kg
 Normal = 6-7ml/kg
Respiratory Rate: How many
breaths you take a minute.
Minute Volume: Amount of
air you breathe in per
minute. Calculated by:
MV = Tidal volume X
Respiratory rate
Vital Capacity: Maximum
amount of air you can
breathe out in one breathe,
after breathing as deeply
as possible = 4.5 – 5 litres.
How much air do we breathe
Total lung Capacity: Volume
in lungs after max
inspiration = 4 - 6litres.
Calculated by:
TLC = VC + RV
Task:
I would like you to
calculate your Minute
Volume.
Residual Volume: Amount of
air left in your lungs after
you breath out as hard as
you can = 1.0 – 2.4litres,
you can never empty your
lungs completely.
MV = Tidal volume X
Respiratory rate
Your lungs and exercise
Your lungs and heart work as
a team to get more O2
round the body and clear
CO2 away. When you
exercise your lungs and
heart have to work harder.
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So what happens to the
lungs to cope exercise?
Your lungs and exercise
During exercise the
following occurs:
1.
Cell respiration in your
muscles increases =
increased levels of CO2
in blood.
2.
Your brain detects this,
sends a signal to lungs to
breathe faster and
deeper.
3.
So gas exchange in your
lungs speeds up. More
CO2 passes out of blood
and more O2 passes into
it.
Your lungs and exercise
4.
The brain also sends a
signal to your heart to
beat faster, so:
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More blood gets pumped
to the lungs for gas
exchange,
More blood gets pumped
to the muscles, carrying
O2 and removing CO2.
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Your lungs and exercise
Look at how breathing changes during exercise:
For an 18 year old … At rest
During
Exercise
Tidal volume
0.5 litres
2.5 litres
Respiratory rate
12 breaths a
minute
30 breaths a minute
Minute Volume
6 litres a
minute
75 litres a minute
Your lungs and exercise
As shown in the previous table, several things happen to tidal
volume, respiratory rate and minute volume.
Task:
In pairs I want you to see whether that is true!
(1)
Count your breaths for one minute while at rest,
(2)
Count your breaths when jogging slowly on the spot,
(3)
Count your breaths while jogging hard on the spot,
raising your knees.
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Get your partner to time you and then swap over to have
a rest between each part.
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What do you notice, is it true?
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http://www.bbc.co.uk/schools/gcsebitesize/p
e/appliedanatomy/